Respiratory monitoring is critical for patients especially those with severe medical conditions which in turn affect the lung and overall pulmonary functions. Respiratory data, such as tidal volume of the lung, can provide valuable information concerning the progression of a disease or injury affecting a patient, which is very useful for assessing, diagnosing and treating respiratory symptoms driven by such disease or injury. For instance, it is proven that post-operative respiratory volume monitoring can help predict the risk of life-threatening complications in post-surgical patients, which may happen hours after the patients are considered stabilized after the operation. Urgent medical resuscitation is essential in such cases to prevent respiratory failure and death.
Nevertheless, respiratory monitoring could also be important for individuals to use during normal daily routines so as to be able to capture respiratory events which may be indicative of a patient's state of respiratory health and reveal adverse conditions which might otherwise go unnoticed. The breathing of babies at risk for Sudden Infant Death Syndrome (SIDS) is difficult to monitor, and accurate non-invasive monitoring at home may be life saving. Obstructive sleep apnea in adults and children requires accurate respiratory monitoring in order to diagnose and treat. Again, accurate non-invasive respiratory monitoring can facilitate this.
Existing monitoring systems and methods are normally complex, inconvenient, and expensive to be effectively and widely used by patients or individuals. For instance, monitoring a patient's respiratory status usually takes place in a hospital setting or a doctor's office, and the patient is normally observed by being connected to cumbersome medical equipment which prevents the patient from freely moving around. Thus it would be highly desirable to be able to easily and accurately measure respiratory parameters in a manner that allows usages in essentially any location.
Such problems have been recognized in the conventional art and various techniques have been developed to provide solutions. For example:
U.S. patent application Ser. No. 13/486,637 (Bernal et al.) entitled “Processing a video for respiration rate estimation” discloses a system and method for estimating a respiration rate by analyzing distortions in reflections of structured illumination patterns captured in a video containing a view of a subject's thoracic region. In one embodiment, a video of a target region of a body of a subject of interest is received. Video image frames are processed to estimate 3D time-series data for the target region. As more fully disclosed herein, the subject's respiration rate is estimated from the 3D time-series data. Measurements can be acquired under a diverse set of lighting conditions. The teachings hereof provide a non-contact approach to patient respiratory function monitoring that is useful for intensive care units and for monitoring at homes, and which aid in the detection of sudden deterioration of physiological conditions due to changes in respiration rates. The teachings hereof provide an effective tool for non-contact respiratory function study and analysis.
U.S. patent application Ser. No. 12/749,861 (Tupin, J R. et al.) entitled “Apparatus and method for continuous noninvasive measurement of respiratory function and events” discloses an apparatus and method for non-invasive and continuous measurement of respiratory chamber volume and associated parameters including respiratory rate, respiratory rhythm, tidal volume, dielectric variability and respiratory congestion. In particular, a non-invasive apparatus and method for determining dynamic and structural physiologic data from a living subject including a change in the spatial configuration of a respiratory chamber, a lung or a lobe of a lung to determine overall respiratory health comprising an ultra wide-band radar system having at least one transmitting and receiving antenna for applying ultra wide-band radio signals to a target area of the subject's anatomy wherein the receiving antenna collects and transmits signal returns from the target area.
U.S. patent application Ser. No. 13/210,360 (Freeman et al.) entitled “Devices and methods for respiratory variation monitoring by measurement of respiratory volumes, motion and variability” discloses devices and methods for assessing a patient. The devices have at least one impedance measuring element functionally connected to a programmable element, programmed to analyze an impedance measurement, and to provide an assessment of at least one respiratory parameter of the patient. Preferably the device includes electronics which aid in calibration, signal acquisition, conditioning, and filtering.